ew interjection earlier than 1978

The exclamation ew has become an instantly recognizable expression of disgust. Used since the late 20th century, it has continued to gain ground in the 21st, perhaps because its two-character brevity makes it so well suited for electronic communication (ew appears almost twice as often as yuck in Oxford’s Twitter corpus). That said, ew isn’t always brief: it can also be spelled euw, and the u or w is sometimes repeated four or more times for emphasis. The earliest evidence of the word found by the OED‘s researchers dates from 1978, in a reporting of children’s speech:

This type of utterance probably existed in oral use for some time before it was recorded, but it seems possible that it may have appeared earlier in a more informal document, such as a screenplay, novel, or even a school yearbook. Can you help us find earlier evidence of ew?

Surely this can be topped easily:
Edmund Schiddel,The swing: a novel – 1975
Maybe he didn’t know. His idea of kicks was to masturbate while watching rats having hatpins stuck through them in the next room.” “Ewww!” She winced. “Don’t tell me things like that!” “I’ll use rat stories to punish you,” he threatened playfully.

Searching for the oral uses, that the OED believes occurred before written usages, throws up some interesting issues.
In the opening song [“Food Glorious Food”] of the [1968] film “Oliver!” [about four minutes in], the fourth boy being served gruel grimaces in disgust and seems to say “Eew” – however:
· is that merely a, very short, old-fashioned “Eugh!” – or a true `early’ use of “Eew” ?
· the http://www.subzin.com subtitle website shows “Eeew” appearing in this film, but at 00:34 – however, [as a telephone then rings, in that transcript] it seems unlikely
In the [1938] film “Pygmalion”, Eliza [around 00:34] looks at an intruding microphone, with disgust/disdain, and seems to say “Eeww” – however:
· as this is where the film is playing with mixed-pronunciations, for comic effect, can her pronunciation be said to be, definitively, “Eeww” ?
· since transcripts / subtitles might be copied [phonetically and/or edited, for screen-space] from the screen, these may not be accurate – whilst published scripts might not note every improvised exclamation made
For a link to a, [claimed] public domain, online version of “Pygmalion”: http://www.youtube.com/watch?v=tmdPj_XbF30